The Jar Scanner Component

The Jar Scanner element represents the component that is
used to scan the web application for JAR files. It is typically used during
web application start to identify configuration files such as TLDs or
web-fragment.xml files that must be processed as part of the web application
initialisation.

A Jar Scanner element MAY be nested inside a
Context component. If it is not included,
a default Jar Scanner configuration will be created automatically, which
is sufficient for most requirements.